Telephone number generator

ABSTRACT

A repertory telephone dialer utilizes a single keyboard with push-button switches which, when first operated while the telephone dialer is in a program mode, select a memory location for storing a telephone number generated by subsequent operation of the push-button switches. When the telephone dialer is in a call mode, the first operation of the push-button switches results in the application of dialing signals to a telephone line in accordance with representations stored at the selected memory location.

United States Patent McCabe et al.

[4 1 Jan. 14,1975

TELEPHONE NUMBER GENERATOR Inventors: Edward J. McCabe; Donald E.

Westphal, both of Wellsboro, Pa.

Assignee: Mek-Tronix Laboratories Corporation, Mansfield, Pa.

Filed: Nov. 16, 1973 Appl. No.: 416,660

US. Cl 179/90 B Int. Cl. H04m 1/51 Field of Search 179/90 B, 90 BB, 90 R References Cited UNITED STATES PATENTS 10/1970 Tate l79/90 B 5/1973 Mardas 179/90 B BOUNCE ELIMI- NATION CONTROL MEMORY ADDRE 8 Primary Examiner-Kathleen Claffy Assistant Examiner-Gerald L. Brigance Attorney, Agent, or Firm-Anthony A. OBrien [57] ABSTRACT A repertory telephone dialer utilizes a single keyboard with push-button switches which, when first operated while the telephone dialer is in a program mode, select a memory location for storing a telephone number generated by subsequent operation of the push-button switches. When the telephone dialer is in a call mode, the first operation of the push-button switches results in the application of dialing signals to a telephone line in accordance with representations stored at the selected memory location.

10 Claims, 12 Drawing Figures PULSE lQFild of the Invention" '231Description1of the Prior -Art TELEPHONE NUMBER GENERATOR iBAC KGROU NDIOI QTHE INVENTION tor,."and ini'particular,toapparatus for generating a multiple digit telephone number, such asja'n eleven digit telephone: number, in response to the selection of a significantlylesser number of digits,such as a single.

cludes many repertory dialers which apply telephone. dialing signals to a telephone linein response to the se lection ofa switch 'corresponding to the telephone SUMMARYJOF; Tiiis INVENTION};

The invention is summariied in'that an apparatus for,

' Q generating signals correspondingto digits of a selected telephone number on a telephone line includes a single 'push button keyboard incIuding ten. push button switches, switch means for selecting a record mode or :a call mode, memory means for receiving and storingrepresentationsof a plurality of telephone numbers in selected locations of the memory means, each'of the I ,plu'rality of the telephone numbers having a plurality of digits, means responsive to a first operation of the push ,bu ttonis'witches when the switchmeans isin therecord 7 mode or the call .mode for selecting a location in the I it jmemory means,means responsive to subsequentfopera M ion-of the push button, switches in accordance with the I selected 'telephone numberwhen the switch means is in 7 the record mode for storing" representationsoftheseilected telephone number in the selected location-ifnth e I. memory means, meansresponsive togthe fieceipt Ofa representation of a digit for producing "signals on the f telephone line corresponding to the received represen;

I .tation of theldigit, and means responsive tothememory location] selecting means'when the switchmeansfjisin the call mode for applying representations offgdigits' y 1. from theselected locationto the signalproducing "m'e'ans. J k I I a Anobject of the invention is to eliminateduplication of keyboards in repertoiytelephone fnumber genera} torsfl" t Anotherobjec't of the invention isto'utilizethecon- V ventional telephone keyboard of ten push buttori' switches to both select a' me'mory location and to get erate representations of selected numbers .to store in theselected memory locationw t I It is also an objectof the invention to eliminate erroneous operation of circuitry in a repertoryrdail er, due to irregularities in switch operation such fas contact j. -65 Additional features of the invention include the pro-* bounce and the like.

vision of a pair of random access memories, one-for 1 storing several telephone numbers to be selectively re- I invention relates to a telephone number genera-.

.s. Pat. N655 3,555,201, 3,665,l13,-.3, 670,1ll, and 3,735,050, in-' called, and-the other for temporarily storing a number as it isgenerated on the telephone line; the provision of a counter circuit for controlling the'size of a memory location forstoring a telephone number; and the provision of facilities responsive of the operation of a hook switch for clearing repertory-circuit function.

' g BRIEF DESCRIPTION OF THEDRAWINGS FIG. 1 is a blockdiagram of a circuit in accordance with the invention; r l FIG. 2 is a detail diagram of a keyboard and encoding circuit of the circuitry in.FIG. l.

'FIG. 3 is a detail diagram of a gate circuit of the cuitry shownin FIG, 1. I

i of the circuitry shown in-FIG. l.

' FIG. 6 is a detail diagram of a read-write address cir-f 'cuit of the circuitry shown in FIG; 1. V t

FIG. 7 is a detail diagram of a memory gating circuit, a counter circuit, and acontrol circuit, of the circuitry] shownin FIG. 1 I I F FIG. 8 is a detail diagram of a function control circuit, a pulse and power circuit, andan oscillator circuit a of the circuitry shown.inFIG..l.-' I FIG. 9 is a detail diagramot a clear circuitincluded in the circuitry shown inFlG. i

no. 10 is a detail diagram of an address gale circuit and a memory address circuit of the circuitry'ofFIG, l

' no. ii is a detail diag am of an automaticf control circuit of the circuitryiof'FIG. 1,] y

gyro. 121s a detail diagram'pfan.automatic "read cir- .cuitinthe circuitry of. l. I v

' 5.1 "f-o'E'sciuPTloN. OFTHE PREFERRED q EMBODIMENT I ,Asigllustrated iii FIG. 1, the invention is embodied in a telephone number generatorIincludin-g a single push representations,encoder c'irc'uit. fo r' generating binary signalsior representations on lines \22 a, 22b, 22c,

, and 22dconne'cted to a gate circuit 24,'an address gate circuit 26, a bounce elimination circuit 28, and aparallel-to-serial converter circuit the latt'erthree .26, 28- V and 30 included in a telephone number repertory circuit 32, identified by the enclosed dashedline. Linesv 34b, 34b, 34c, and 34d connectoutput's of an automatic readcircuit 36 in the repertory circuit 32 to inputs of thegate-Tcircuit 24 which has outputsiconnected by 'liries 38a, 38b, 38c and 38d to inputs of am'emory 40 r I a number, signal generatori4l,enclos ed by dashed lllines. A function control circuit 42', fha ving inputs on I lines 44, 46 and 48 from a pulse and power'circuit 50, "has outputs connected by line'52 to the gate circuit 24,

by line 54 to the automatic readcircuit 36 and'an automati'e control circuit 58, and by line 56 to the auto- 'matic control circuit 58. The number signal generator 41 in response to signals or representations of digits on jlines 38a, 38b, 38c and 38d is capable of producing a telephone number signal on telephone lines, identified TIP, GRDand RING, connected to a telephone system (not sho wn)LThe function control circuit 42 has (a) a manual mode for enabling the gate circuit 24 to pass mode for enabling the repertory circuit 32 to store, at

lection of an address by the push button encoder 20.

parallel inputs thereof to serial binary signals on a serial output of the parallel-to-serial converter 30. The line l22is connected to a clear input of the parallel-toserial converter 30. Additionally, the converter has a preset input and a clock input. A suitable parallel-toserial converter is model No. S 5494, four-bit shift register sold'by Signetics Corporation.

In; the number generator circuit 41, the memory 40 is a read-write or random access memory having four parallel binary data inputs, four parallel binary outputs, address or select inputs, a memory enable input and a write enable input. Integrated circuit memories, such as model number MCM 4064 sold by Motorola, Inc. and

. model no. Ser. No. 7489 sold by'Texas Instruments,

Inc. are suitable.

The 'line 44 from the pulse and power circuit is connected to a clear circuit 62 which has outputs connected byaline 64 to a read-write address circuit 66 and an output control circuit 68, and by a line 70 to a countercircuit 72 for initially clearing the number gen- 3 erator circuit 41. I

Lines 74a, 74b, 74c, and 74d connect outputs of the read-write address circuit to the address inputs of the memory 40. The lines 38a, 38b, 38c and 38dare connected toinputs of a bounce elimination circuit 76 ditionally, the line 78'is connected by an inverter 87 I7 and a line-89 to inputs of the read-write address circuit 66 and the output control circuit 68.

Inverted outputs-of the memory 40 are connected by lines 90a, 90b, 90c and 90d to a gatecircuit 92. Aline 94 from the output control circuit 94 is connected to an input of a strobe pulse generator 96 which'has its output connected by line 98 tothe gate circuit 92'. The

outputs of. the gate circuit 92 are connected by lines. 100a, 100b, l00c-and 100d to inputs of a counterci'r-j the memo'ryl-50. Theda'taoutput of the memory 150 i .is connected by line 156,to an input of the automatic The automatic control circuit 58 has outputs connected by lines 124 and 128 to theautomatic read circuit 36, by lines 129 and 131 to the preset input and the clock input respectively of the parallel-to-serial converter 30, and by lines 134 and 136 to the memory address circuit 120. Inputs of the circuit 58 are connected to line 126 from the automatic read circuit 36 and to lines 130 and 132 from the address gate circuit 26. Outputs of the address gate circuit 26 are connected by lines 132, 138a,'138b,, 138c and 138d to the memory address circuitv 120. A line 144 from an output of the automatic control cicuit 58 and a line 146 from the serial data output of the parallel-to-serial converter 30 are connected to respective inputs of a NOR gate 148 which hasits output connected by line 152 to a serial data input of a memory 150.

The'memory 150 is a 1,024 bitstatic random access memory, suchas model number 2602 from Signetics Corporation, having binary storage locations which'are randomly. accessed by the signalson the address inputs the memory. 150, Line'153vconnect's an output of the automatic controlcircuit'58 to the read-write input of cuit 72which has outputsconnectedb y lines 10211, i

102b, 1026 andl02d'to the output control circuit68.

The output control circuit 6 8 has an output connected by line l04 to an input of the read-writeiaddress circuit 66 and the NOR gate80 and has'an" inputconnected to a-line 107 from anoutput of the 'read write addresscircuit 66. Another output of the output control circuit 68 is connectedbya line108 to an oscillator circuit i which in turnhasits output" connected by line 112 to inputs of the pulse and power circuit 50 and-the j.

counted'circuit7-2 jl he pulse and power circuit50 is connected to thetelephone-lines TIP, GRD-and RING. v In thetelephone number repertorylcircuit 32, a line U 114 from the function control circuit 42 is connected A to'aninput of'a-clear circuit 1 16 which has outputs con- I f nected byline 118 to a memory address circuit 120, the addressi'gat'e circuit 26, theautomaticfr'ead circuit 36, and the automatic control circuit 58, and by line. 122

i I to the memory address circuit and the parallel-toserial convertercircuit 30 for initially clearing the repertory circuit32. A line 123 from thebounce elimin'ai puts ofthe gates 168a, 168b, 1686 and 168d are con- "tion circuit 28. is connected to inputs of thejaddress gate circuit 26 and the automatic control circuit 58'. A

line from the automatic read circuit 36 is con-- tains a keyboard or keypad with. ten normally open ,push' button s'witches158a through l58j which are conn'ectedbetwe'en ground and various inputs of NAND gates a, 1460! 160c and 160d in: a binary encoding arrangement iThe inputs off the N AND gat,es ;160a,' .il-60;b-,'160jc and 160d are normally. biased through resistors162d (onlyone'shown)-throughl62j..'Each of the push button switches l58a;through 1 58j corresponds to I one of the telephone. digits, 1,2,3,-4,5,6,7;8,9',0 which are selected toform telephoner' umbersi'Theencoding network, connectingthe' switches1j58i1-through l58j to v the inputs of the NAND, gates'160a, l60b, 160c1and 160d, isfO'rmedtoprdduce binary coded signals on output lines '22a,.22b, 22c and 22d'connected to outputs of'the-NAND- gates 160a, 160b, 1606 and 16011, which 1 signals arethe .twos complement of the selected digit,

assuming'thatthe digit 0 corresponds to decimal 10. 1 The gate circuit 24-, shown-in FIG. 3,-has NAND gates 168a, 1168b, 168-caridxl68d with first inputs connectedto' the "respective lines 22a, 22b, 22c and 22d and second inputs connected tothe line 52. The outnected to respective inputs' of NAND gates2170a, 170b,

ased through resistors 172a, l7-2 b il72c and 172d conv nected to voltagetermina l outpu softhe to the respe'ctiveilines 38223812; 38c and 38d. The bounce,elimination-circuit28yillustrated in FlGg" n 4, hasa NOR gate I174Fwith :a first input connected top.

the line' 221i, andfa, second input connectedto the line- 4 1 I Soto the line 104. The outputs of the NAND gates 216a, 5 216b, 2160 and 216d are connected to the respective nected to line 22c.and asecond'input connected to line I 22d. The outputs of e NQRl gates" 174 and 176 are connected torespective inputs "ofta NAND function r gate1'78 which; hasits output connected to an input of a oneshottl 80"andanvinput of a-NAND gate 182. The

output erthe on'e'shot 1 0 is edhheeted to a differentiating circuit includin'ga' series capacitor 184 connected tothejuiflfiQIijQftWo serially connected resistors 186 and connectedbetwee'n a voltage terminal 190 and .An advance input ofa read addresscounter2l2 is connected to the line 104 across a noiseeliminating and "delay capacitor 214. The counter 212 has outputs connected to the respective first inputs-0f NAND gates NAND gates 216a, 2 l6'b,2 l6c and 216d are connected lines 74a, 74b, 74c and 74d which are biased through resistors 218a, 2181:,2186 and 218d coupled to the voltage terminal 164. Reset inputs of the write address V counter208 and the readaddress counter 212 are conn cte -to he line 64.

"The outputs of the writefaddr ess counter 208 are connected to first inputs of respectivefNAND gates 220a, z ,-200e and 220g, while the outputs of the re thalfjrhe .juhetieh of titer-resist rs 186 and 188 is connectetl to thef second'input of the NAND gate 182,

whichhasan output connected to line l 23. Various caj pacito'rs, resistorsiand biasing. terminals, such as termij nal19l, are sh0wn connected toanintegratejd circuit I unit to 'form the one ishot-180iina conventional inans ner; suchinannerof' connectingcapacitors, resistors read 'addresscounter 212 are connected to first inputs of respective NAND gates 220b, 220d, 220f and 220k.

Inverters 222a, 222b, 222g and 222d'couple the outputs-ofthe write address counter 208 to second inputs of respectivejNAND gates 220b, 220d, 220f and 22011 and biasing terminals beingf well k nown in the art and described in the various manuals to produce a one shot circuit with asuitable outputsignal fora suitable durat I Q Thetstrobe'pulse generator196,"l?lG: l'islsubstantiallyv v similarto the'strobepulse gene'ratorS QXgjept that-the inputs of the strobe pulse generator 96 are from line 94 s H 240can'd-240d ai1econnected totheli-ne70.

and the'putputiison line ji- 4 includes a writeaddressco nter 208-havinganadvance input connected-to th'ei yp e' delay-- circuit. The

v roduc'e a'delayedshortiduration pulse @or signalf'on the ne -88 connected, ,tothe junction of'the f; 1 j re sistors'202 and 204"for allowing thevarioustcircuits to stabilize 'pr iorto writing infftheirnerrjiory40;- Q

tion. The duration, of output signal from'the'one shot q 180 is se lect ed to exceed the d urationf that the push button switc hes 158a throughtl58j, EIQQ2, produce irev regularities due to contact bouncerand thelike in 0peration of the push,buttonswitehesgand is selected to be substantially less than thejleast normal operation time t of one of the push;button'fswithces;1 58q'throught-l58j. The bounceleliminationj"circuit jo of FIGQI ji s suli-Q 'stantially the same as thebounce elimination circuit 28 dress counter;2 12;." I I, t p r t As shown'inkFlG 'l, thegate circuit 92 includes NOR Ygates 23041,?230113-2300and 230d,which have first ins whilcinverters 222?,222f, 222g, and 222h couple the respective outputs of the read address counter 212 to second inputs of respect'ive NAND gates 220a, 2200,

220s andjv220gt The outputs of the NAND 'gates 220a through 220hflar'e'coupled to an input of an inverter 224 which isbiased through a resistor 226 connected to the voltage terminal1 64. The read-write address circuit 66fisdesig ned to producea signal on line 107 if the address onfthe outputs of the write address counter 208 is the sameas; the address onthe outputs of the read ad- 7 puts connectedto the'lin'es 90a, 90b,- 90c and90d. Pairs 'of'resis'tors 232a -and 234af232b and 234b, 2152c and 234C, and 23221 and 234d connectedfserially between .thevoltage terminal T64Yand groundihave junctions connected to} respective lines90a, 90b 90c and 90d for biasing thejl nes,Second inputs of the NOR gates 98. The outputs ofthe NORigat'es2 3 0a, 230b, 2306 and "230d are connected 'bY-inverters 236a, 236b; 236 c and an output the flip flop 2401) is connected to the input of the flip-flop 240 cgand an'butputfQfflip tlop, 240a isconnectedto an input of the flipl-flop 2 d, such that the counter -72- counts down withi' 'each ,pulse on :line

t ythe writeaddress counter;208a'reconnected tofirst in r puts OfZ NAND-gat esZIOa; 2101):, 210c and 210d! Sec ond inputs of the NAND gates 2l0a;2l0b,2l0c,"-and" 2l0dare connected to the line' 89 while-the outputs of connected to forrnf thejbir'iary counter'72. J and K inflop 240a is connected to an: input of the flip-flop'240b,

112.; set let "preset? inputs'of the nipne sfuoe; 240b,

The utp'uts fithe flip-flops 2401i, 240b, 240c 240d are connected by the respective lines 102a, 102b, 102s andt102 d to inputs of aNAND gate 242 in the output control circuit 68LThe output of the NAND 51gat 242 i e heet 'dby the line 108 to the firstinput :pef NoR gate 244 while a second inputt ofthe NOR gate 244 is connected to th'line64. The output of the NOR gate 244 isconnected to afirs't input-of a NAND g afte 246.Also the line 108 is connected to inputs of a one 'shot circuit 248 which has)its'output'connected to and a second input of the NAND gate 246. A third input of a NAND gate 246 is connected to the line 107. Inputs of a one shot 250 are connected to the output of the NAND gate 246 and to the output of an inverter 252 coupled to the line 89. The one shot 248 is designed to produce a pulse output which has a duration corresponding to the desired duration between successive pulse trains in signalling a telephone number. The NAND gate 246 enables the operation of the one shot 250 in the absence of an output signal from the one shot 248, the presence of signals on all of the lines 102a, 102b, 1020 and 102d and the absence of a coincidence signal on line 107. Outputs of the one shot 250 are connected to the respective lines 94 and 104.

The oscillator 110 is shown as including an integrated circuit unit 254 to which is connected resistors and a capacitor as well as the voltage terminal 164 and ground to produce an oscillator capable of generating pulses having a frequency and duty cycle suitable for pulsing a telephone number on a telephone line. The line 108 is connected to an enable input of the oscillator unit 254 while the line 112 is connected to the output of the oscillator unit 254.

In the pulse and power circuit 50 the line 112 is connected by resistor 276 to the base of a grounded emitter transistor 278, which base is biased by a resistor 280 connected to ground. The collector of the transistor 278 is connected to one terminal of a relay coil 282 which has its other end connected to the voltage terminal 164. The coil 282 is part of a relay indicated generally at 284 which has normally closed dial pulsing contacts 286 connected to terminals 288 and 290 and a telephonecircuit 292. Normally open contacts 294 of the relay 284 are connected to terminals 296 and 298 which are connected in parallel with the receiver in the telephone circuit 292 across the terminal 290 and normally closed contacts 308 of a hook switch 309 in series with terminal 310 and the RING conductor of the telephone lines. A series combination of a resistor 301 and a relay coil 302 of a relay, indicated generally at 303, and a diode 304 across the resistor 301 and coil 302 are connected in series with the terminal 288, dial pulsing contacts 286, terminal 290, the telephone receiver and normally closed contacts 308 across terminals 307 and 310 connected to respective conductors TIP and -RING of the telephone lines. Contacts 313 of the relay 303 are connected between the line 44 and the series circuit of normally closed contact 315 and a contact arm 316 of the hook switch 309 to a positive terminal of a battery 317 to supply voltage to the line 44. The resistor 301 and the relay coil 302 have impedence values which are sufficiently small not to interfere with audio signals to the receiver. The diode 304 has a polarity across'the resistor 301 and the coil 302 such that the diode 304 shunts the resistor 301 and coil 302 during the dialing period until the called party answers and the polarity of the voltage on terminals 307 and 310 reverses.

The battery 317, when the receiver is replaced operating the hook switch 309, is connected through the contact arm 316, a normally open contact 318 and line 48 for providing a charging currentto the battery 317. A diode 320, connected to ground and the negative terminal of the battery 317, is connected to the RING conductor ofthe telephone lines to complete the charging path for the battery 317 when the telephone is not being operated. A zener diode 321 is connected across surges. Line 46 is connected to terminal 307 and the TIP conductor.

In the function control circuit 42, a contact arm 324 of a manual or automatic mode control switch, indicated generally at 326, is connected to the line 44. The switch 326 is a manual switch which can be operated to connect the contact arm 324 either to a contact 328 or a contact 330. Contact 328 is connected to line 52 and across a resistor 332 to ground. Also the line 44 is connected to the voltage terminal 164 and by a resistor 333 to the bias terminal 241 to form the source of power for the terminals 164 and 241. The contact 330 is connected to the line 114, the voltage terminal 190, contact arm 334 of a program switch indicated generally at 336, and by a resistor 337 to the bias terminal 191. Contacts 338 and 340 of the switch 336 can be alternately engaged by the contact arm 334. The switch 336 also includes a contact arm 342 connected to the line 48, and contact 344 connected by resistor 346 to the line 46. The resistor 346 is selected to limit the charging current through line 48 to less than that which would indicate to a telephone system that a receiver is lifted. A contact 348 selectively engaged by the contact arm 342 is also connected to the contact 330. The switch 336 is such that the contact arm 334 engages the contact 338 and the contact arm 342 engages the contact 344 with the switch 336 in a call or dial position, and the contact arm 334 engages the contact 340 and the contact arm 342 engages the contact 348 when the switch 336 is in a program or record position. The contact 338 is connected to the line 54 and across resistor 350 to ground while the contact 340 is connected to the line 56 across a resistor 352 to ground.

The clear circuit 62, illustrated in FIG. 9, includes a resistor 356 connected between the line 44 and a capacitor 358 to ground. The junction of the resistor 356 and the capacitor 358 is connected by a zener diode 360 to the base of a grounded emitter transistor 362 which has its base biased through a resistor 364 to ground. The collector of the transistor is connected by a resistor 366 to the voltage terminal 164 and to inputs of a one shot 368. The outputs of the one shot 368 are connected to the respective lines 64 and for producing opposite polarity clearing pulses on the lines 64 and 70 when voltage is initially applied to the line 44.

The clear circuit 116 is substantially similar to the clear circuit 62 except that the input is on line 114 and the outputs are on lines 122 and 118.

The address gate circuit 26 is shown in FIG. 10 and includes a NOR gate 372 having a first input connected to the line 123 and its output connected to first inputs of NAND gates 374a, 374b, 3740 and 374d. Second inputs of the NAND gates 374a, 374b, 374C and 374d are connected to the respective lines 22a, 22b, 22c and 22d. Inputs of a NAND-function gate 376 are connected to outputs from the respective NAND gates 374a, 374b, 3740 and 374d. The output of the gate 376 is connected to the clock input of a flip-flop 378 which has its output connected to the line for producing an output signal at the trailing edge of the first digit applied to lines 22a, 22b, 22c and 22d to disable the NOR gate 372 and prevent further signals from passing through NAND gates 374a, 374b, 374a and 374d until a clear signal is applied over line 118 connected to a clear input of the flip-flop 378.

Y 394 and theft'lip-flop 396;

In the memory addressing circuit, the line 132 is connected by an integrating type delay circuit, including a series resistor 380 and a capacitor 382 shunted to ground, to an input of a one shot 384. A binary-todecimal 'decodensuchas model No. S 5442 from Signetics Corporationyhjas inputs connected to the lines 138a, 138b, 138cand 138d. Outputs of the decoder 386, corresponding to the decimal numbers 2 through v 10, are connected to various inputs of NAND-function gates 388a, 3881:, 388e,, 388d, 388e, 388f, 388g and 388k in a coding arrangement designed top'roduce binary outputs .onthe. gates 338a through 388k for each of the signals on the outputs of the decoder 386 separated by 44 binary counts; Four-stage up-down binary counters 392 and 394, such as type SN 54193 from Texas Instruments, Inc., and a flip-flop 396 are connected in a .binarycounting arrangement to form a nine-stage binary counter '397which isadequate to count the 440 addresses required to store binary coded representations of tentelephone numbers of eleven digits each. The negative going output of one shot 384 is connected to the load inputs of the counters 392 and i connected through a NAND gate' 398 andan inverter 400 to the clear input of the flipeflop 396. Outputs of the jcounters 392 and 394, and the output .of the flipflop 396 areconnected to'thelines 154 a, 154b, 154e,

I 154d, 154e, l54f, 154g, l54hand 154i (collectively referred to in FIG. 1 as lines 154) to apply memory ad- "dress signals thereon. Clear inputs of the counters 392. r

and 394 are connected to the linei 122-while the line 118 is connectedto a second input oflthe NAND gate 398 to clear an'y address storedinthe counters392and nents such as resistors and capacitors for producing a series of pulses at a high rate relative to the dialing pulses and push-button operation; The output of the oscillator 426, biased by a resistor 427 to the voltage terminal 190, is connected by'an inverter 428 to an input of the first flip-flop 414a in the counter 416 to advance the counter 416. Also the inverter 428 is connected to the first input of a NAND gate 430 whose i r 396 and the clockinput of-the flip-flop 396. The positive-going output of the one shot 384 is connected to I the first data input; of the counter 392 while the outputs .The automatiocontrol circuit 58jsh owri inFIG. 111

i has a NAND gate404 with one input connected to the line 56 and a second input connected to the line 132.

The output of'the NAND gate 404Jis connected through a differentiating circuit includinga series ca- 1 'pabitor406 connected to the junction ofresistors408 and 410 connected serially between the voltage termim1 190 and ground. The junction of the'resistors 408 and 410is connected to one inpu'tof a NORgate 41'2 I which has its outputconnected to clear inputs of flipnected in a binary counting arrangementto form a64 and 4l4f are connected "to' inputs of a' N-AN-D; gate14'20 M to" render the output at the NAND gate 421! 16w. when; f

ever thecount in the counter 4l6freaches 44. ff. Q The output-"of, the NAND? gate 420'itmmwed tofa' first ifipu dra NAND. gate T422 which thasflitsloutput I co n nected toan input of a NAND-funetion. gatej424i' connected to a controlling input of an oscillator426k The oscillator 426 is an integrated circuit with compooutput is connected by the line 134 to up input of the m mmies: (FIG. 10 A NAND gate 432 has a first inputlconnected to the output of the NAND gate 420, a second input connected to line 56, and an output connected to the clock input of a flip-flop 434 interconnected with :a flip-flop 436 in a binary counting arrangement. The 6 output of the flip-flop 434 is connected to the clock input of the flip-flop 436, a second input of the NAND gate 430 and to the line 144. The

Q output of the flip-flop 434 is connected to the first input of aNAND gate 438 which has its second input connected to the output of the inverter 428. t

The Q output of the flip-flop 436 is connected to the J-K inputs of. the flip-flop434 to disable the flip-flop- 434 when it returns to its initial state. The output of the NAND gate 438 is connected by the line 136 to the down input of the counter 392 (FIG. 10). Lines 134, 13.6 and 56 are connected to inputs of a NAND gate 442 which has its output connected by an inverter 444 to a differentiating circuit including a capacitor 446 to the junction of apair of resistors 448 and 450 con-" nected across the voltage terminal 190 and ground. The junction of the resistors 448 and 450 is connected v.

i to the line 153. Line 118 is connected to clear inputs of the flip-flops 434 and 436 and to preset or set inputs Line is connected to a first input of a NAND gate 456 while theline. 123 isconnected by an inverter 458 to a second input; of the NAND gate 456. The output of the NANDgate 456 biased by a resistor 460 to the voltage terminal '190 is connected to an input of a one shot.462'which;has an enable input connected to line 56. The output of the oneshot 462 is connected to the line 129.'Also the output of theNAND gate 456 is connected byan inve'rter464 to a clock input of a flip-flop 466. The negative-going output of the flip-flop 466 is connected to the secondinput of the NAND gate 422 while the positive-going output ofv the flipflop 466 is connected to the first'input of a NAND gate 468 which has its output connected to a second input of the NAND-function gate 424. Also the negative-going output of the flip-flop 466 is connected to an input of a one shot 470 which has its output cor nected to a second .input of the NOR gate 412.'The-Q output of the flipflop434 is connected to a second input'of theone shot The output of the NAND gate .456 is connected throughfian integration type delaycir cuit, including a series resistor 472ficonnectedlto fia c'apacitor 474 shunted to ground. toa'n input ofa'one'shot 4'16 which I has'ione output connected, to 'ajsec ond input of NAlflD gate 468. .The on'efshot'476 is selected to produc'ea pulse duration equal to the timelof four pulses from the oscillator 426. The output of the NANDgate 1420 is connected to a differentiating circuit including a serial capacitor 478 connected to the junction of apair of resist'ors 480 and 482 in series between the voltage termi nal 190 and ground. The junction of the resistors 480 and 482 is connected to the clear input of the flip-flop 466.

The line 54 is connected to a first input of a NAND gate 484 while the second input of the NAND gate 484 is connected to the output of the inverter 458 from the line 123. Another output of the one shot 475 is connected to the line 124 and the line 126 is connected to a second input of the one shot 476. Also the output of the inverter 428 is connected to the line 128, while the output of the oscillator 426 is connected to line 131.

The automatic read circuit 36, as shown in FIG. 12, has a NAND gate 490 with a first input connected to the line 54 and a second input connected to the line 128. The output of the NAND gate 490 is connected to clock inputs of flip-flops 492a, 492b, 4920 and 492d interconnected as a shift register 494. The line 156 is connected by an inverter 496 to the first stage 492a of the shift register 494. The line 54 is connected to an enable input of a one shot 498 which has a trigger input connected to the line 124. A first output of the one shot 498 is connected to first inputs of NAND gates 500a, 500b, 5000, and 500d while second inputs of the NANDgates 500a, 500b, 5000 and 500d are connected to respective outputs of the flip-flops 492a, 492b, 4920 and 492d in the shift register 494. The outputs of the NAND gates 500a, 500b, 500 c and 500d are connected to the lines 34a, 34b, 34c and 34d. A second output of the one shot 498 is connected to the line 126.

Operation In operation of the telephone number generator, shown in FIG. 1, an operator by the function control circuit 42, shown in FIG. 8, selects the mode of operation of the dialing apparatus. Through the switch 326 the operator selects either a manual mode or an automatic mode, and by the switch 336 the operator selects either a dialing mode or a program mode when the switch 326 is in. the automatic mode. When the switch 326 is in the manual mode, the operator by operating the push botton switches 158a through 158j, FIG. 2, in accordance with a selected telephone number causes the number signal generator 41 to generate corresponding number signals on the telephone lines. When the switch 326 is in the automatic mode and the switch 336 is in the program mode, the operator by depressing a first selected one of the switches 158a through 158j selects a particular one of ten storage spaces in the telephone number repertory circuit 32 into which the operator wishes to store a selected telephone number; subsequently, the operator by depressing the switches 158a through.l58 j in accordance with the selected telephone number programs or stores the selected telephone number into the selected storage location. When the switch 326 is in the automatic mode and the switch 336 is in the dial mode, the operator by first depressing a selected one of the switches 158a through l58j selects a pre-programed number which is to be automatically dialed; the operation of the selected button causing the telephone number repertory circuit 32 to operate the number signal generator 41 to generate corresponding number signals on the telephone lines.

In the number signal generator, the lifting of a handheld receiver of the telephone from the hook switch 309 applies a power signal to the line 44 which operates the clear circuit 62, applying clear signals to lines 64 and 70 clearing the counter 72, the read-write address circuit 66 and the output control circuit 68.

The application of a binary coded signal to lines 38a. 38b, 380 and 38d is sensed by the bounce elimination circuit 76 to produce a signal on line 78 which is applied by the NOR gate 80 to the memory enable input of the memory 40. Also, the signal on line 78 operates a strobe pulse generator circuit 86 to apply a write signal to the write enable input of the memory 40 to record or store a representation of the binary coded signal on lines 38a, 38b, 380 and 38d in the first memory location selected by a write address signal produced on lines 74a, 74b, 740 and 74d and a signal on line 89 from inverter 87 applied to the read-write address circuit 66. Upon the trailing edge of the signal from the inverter 87 on line 89, a write address portion 89 of the readwrite address circuit 66 is advanced to the next write address in the memory 40 in preparation for storing the next number applied to the lines 38a, 38b, 38c and 38 d. Also at the end of the signal on line 89 the output control circuit 68 produces a read signal on line 104 which is applied by the NOR gate 80 to the memory enable input of the memory 40 to generate the data signals stored in the first memory location on the outputs of the memory and apply them to lines 90a, 90b, 90c and 90d. Also, a read signal is generated on line 94 which causes the strobe pulse generator circuit 96 to apply a strobe pulse over line 98 to the gate circuit 92 gating the data from lines 90a, 90b, 900 and 90d over lines 1000, 100b, 1000 and 100d to inputs of the counter circuit 72. The outputs of the counter circuit 72 apply signals to lines 102a, 102b, 1020 and 102d which are sensed by the output control 68 to be a nonpredetermined count to generate a signal on line 108 which initiates operation of the pulse oscillator circuit 110. The oscillator 110 applies pulses to line 112 which operates the pulse and power circuit 50 to generate trains of pulses on the telephone lines. Also the pulses on line 112 are applied to the counter 72 which changes the count in the counter 72 until the counter 72 reaches the predetermined count to operate the output control circuit 68 and terminate the control signal on line 108 and the operation of the oscillator 110. At the termination of the read signal on line 104, a read portion in the read-write address circuit 66 is advanced to the next memory location to be read. In the event the next read address is the same as the last write address, the read-write address circuit 66 produces an output signal on line 107 which prevents the output control circuit 68 from producing read signals on lines 104 and 94.

When the function control circuit 42 is in either the automatic program mode or the automatic call mode, the gate circuit 24 is disabled through line 52 to prevent signals on lines 22a, 22b, 22c and 22d from passing to lines 38a, 38b, 380 and 38d. When the function control circuit 42 is placed in the automatic program or automatic call mode, the function control circuit 42 produces a signal on line 114 which operates the clear circuit 116. Clear signals from the clear circuit 116 on lines 118 and 122 reset the automatic control circuit 58, the memory address circuit 120, the address gate circuit 26, the parallel-to-serial converter 30, and the automatic read circuit 36. The first operation of the push button encoder circuit 20 applies a corresponding binary signal over lines 22a, 22b, 220 and 22d to the inputs of the address gate circuit 26 and the bounce elimination circuit 28. A pulse signal on line 123 from bounce elimination circuit 28 operates the address gate circuit 26 applying b n to'address inputsof th 1; co der 20.2.

ary signal on lines 221,221),-

22c and 22dover liriesi1381ii,: 13 8b, "138p and 1384 to l the memory addresscirc'uit 120, The addressgate circuit 26 is set by th'eftrailing'edge of the first-binary sig- F nals appliedtolines 138a,'1:38b,138cand'138d'for preventing passage of sub'sequentsi gnals from lines 22a,

22b, 22c and 22d to lines 113 8tz, 138b, 138C and 13811.

c i Also, the setting of the 'address gate circu it26 produces a signalron line130-enabling the automatic control cir- I cuit 58 to control subsequent stepsi' Thejmemory ad-; 1 dress circuit 120 applies" address-signalsover lines 154 ememqry iso to select" amem-i l ory 'location. "w I When the line 56 hasa-signalthereon from the selection of the automatic prog-ram jrnode by the function 36"a'pplies a signal over line 126 to the automatic control circuit 58 to initiate another cycle of reading the next serial binary codednumber from the memory lliintoth e automatic read circuit 36. The repertory circuit-32will thus continue to read out serial binary numbers from the memory 150 and apply parallel binary, numberstothe number signal generator 41 until -theme mory. address circuit has been stepped through-'44 addresses; thus, a telephone number containing ele'ven telephone digits stored in' the memory 'canfbe readoutfl'and applied-by the number signal control 42, a signal on line 1 32 cat'ises the'automatic I through clocksignals orr line 136 while erase signalsare applied over line 144 through gate 14$;and line -152 to control circuit58'to step th'eimernory addresscircuit up through clock signals on :Ii'net 134 andfthen down i generatorl4lto thetelephone lines in response to the selection of a single push button in the push-button encoder 20. "Referring to-F1G.2, the depressingof one of the switches. 158a through 158j connects selected ones of inputs of NAND gates 1601:, b, 160c and 160d to groundto produce corresponding high-level outputs and signalson1lines22a, 22b, 22c and 22d. The dial the data input of the memory ISOLS irnultaneoustothej Y erase signals, write signals are appliedove'rkaline 153 to theread-write inputthememory' 159th clear a memor block'to receive a corresp ondin'g' telephone numnumber gatef 24 of 3 gates the signals on lines 22a, 22b, 22C and 2221 through NAND gates 1680,1681),

168a and 168d "if'a manual mode selection signal is present on line 52. The outputs of the NAN-D gates 168a, 168b,1l68cand168d'are passed through the The subsequent binary coded decimalsi gnal'son lines 22a, 22b, 22cand 224 selected by thei pushbott'on-encoder 20 in accordance with the desired tel eplione number to be stored in the memory l50-are applied to inputs of the paralleI-to-serial converter 30.?The auto- I inatic control circuit 58 in response to the bounce elimf NAND gates a, 170b,]170c and 170d to linesv38a, 38b, 38c and 38d and hen'ce to the data inputs of the memory40 in FIG. 1. If the line 52 is biased low,

" l NAND" gates. 168a, 168b, 168C and 16811 are disabled ination circuit 28 applyinga signal onflineal23'pro duces a presetsignal on line 120Itemporarilys'torin'g the binary coded decimal digitin the 'pariallelz-toj s'erial converter 30. Thereafter; clock signalsare applied to,

lines 131, 134 and 153 bylthe automaticcontrolcircuit 58' to write the four digits from serialoutput-of the parallel-to-serial converter 30 through une 146, the" NORgate 148' and line 152 into the zmemoryt 1sflas'ad- 1 When the "line 54 m asignal-thereon as aresult of] l y "the selection of the automatic call mode byith' func-f- ,tioh-cblritrol circuit 42,,the signalon' line130 ,atfthe end I fof'thefirst bin'arysignalsapplied 10 lines 2 2a,,22b, 22c Q and 22d causes' theautomatic control circuith58 to apply four clock signals ove'r'fline's134 tostep the rnemr f *ory address circuit 120, to cause the meory 150w apply four serial binary digitsco'rresponding we digit'of a" telephone number over line 156 to aninputoftheau'to} matic read circuit 36.-Clock signals over line128'f r'om I the automa tic control circuit stores the binary number 7 on line 156 in the automatic readcircuit 36.Then a sig l V 'nalon line 124 operates :theautomatic read circuit 36 .togapply the binary coded'n'umberin parallel'fo'rm from 1 the/automatic read circuit 36 to lines'34a, 34b, 34cand 38b, 38c and 38d causing the; number signalgenerator 41 to'apply telephone nurn bersignaIs to thetelephone" v lines. After applying the parallel binary coded'signals vtoilines-34a, 34b, 34c and 34d, the automatic read cirdress circuit 120' rsstepped in synchrdnism to select"49 'tourserialmemory addresses inthe memor /s50.

the four digits-tin the parallelrto-serialj'converter 3 I ,have been writte'n'inf control circuit 58 terrr li z on lines 131, 1 453113453,gthus"preparing"theicirc'uit for the n'eiit digitto to prevent the signals on the lines 22a, 22b, 22c and 22d from being applied to the inputs of the memory 40.

Whens'ignals arelinitially appliedto' the bounce elim-, j-inationcircuit 28, shown in FIG. 4, signals through the N ORlgate s 174 and- :176 produce an output on the lNAND-function gate" 178 which triggers the one-shot 180 for a predetermined duration. At the'trailing edge ,of'the output-of the one-shot'180 a positive going pulse producedby the differentiator circuit isapplied to the input ofthe NAND gate 182 which has its other input connected tothe output. of the NAND-functio'n gate 1' 78. Thus;"the]NAND ygate l82'produces a suitable ShQl't duration pulse indicating the initiation and presceiof a signal'con lines 22a,- 22b,- 22c and 22d after the period in which-the switches-158a through 158j tend to bounce or produce irregular signals. Additionally, the "pulse outputofNA ND' gate- 182 continues-only for a I durationwhich is substantiallyless" than the normal du- ;.from push-button switches. Referringto' FIG, 5, the

ration 'ofithe'closu re or thefsvvitches 158a through l58j to avoid irregularities'in the operation of the telephone number generator-occurring upon the opening of a selectedswitcht'lThe bounce elimination circuits 28 and 76 of FIG. 1 avoid'the -erroneo us recording of data in the memories 40 and l50due to irregularities in signals g strobe pulse generator 86 produces adelay'ed-pulse signalresulting from a delay inthe charging of capac'itojr l96 to operate the inverter '198 which then generates a' short pulse output through the differentiator circuit. Thus, th'e.st r obe p'ulseoutput from; .the strobe pulse generator 86 is delayed by an amount determinedby the resistor 194 and the capacitor 196 and has a short duration determined by the ca mpacitor 200jandthe iresi storsi202 and 204.; V

Referring to FIG. 6, the writeaddresscounter 208 andthe read addresscounter=2l2are reset to their zero w countslby the clear signal on line 64. A write signal on line 89 operatesthe NANDgates 210a, 210b, 210C and 210d to apply'the output of the write address counter to the lines 74a, 74b, 740 and 74d. At the trailing edge of' the write signal on line 89, the write address counter 208 is advanced to the next address or count. Similarly, the read signalon line 104- operates gates 216a, 216b, 2160 and 216d to apply the output of the read address counter 212 to the lines 74a, 74b, 740 and 74d. The trailing edge of the read signal on line 104 advances the read address counter 212 to the next address or count. When the outputs of the write address counter 208 and the output of read address counter 212 are the same, the outputs of NAND gates 220a through 22011 will all be high producing a'coincidence signal on line 107 to prevent further operation of the number signal generator 41 (FIG. 1) until another number has been written in memory 40. The non-coincidence of a signal on an output from the write address counter 208 with the respective output of the read address counter 212 causes one of the NAND gates 220a through 22011 to produce a low output thus producing a high output on line 107 indicating the non-coincidence of the write address counter 202 with the read address counter 212.

Referring to FIG. 7, the presence of a high input on all of the inputs of the NAND gate 246 as well as the absence of a write signal on line 89 to the inverter 252 and the enable input of the one-shot 250 allows the one-shot 250 to trigger producing read signals on lines 104 and 94. The delayed strobe pulse on line 98 resulting from the read signal on line 94 is applied to the inputs of the NOR gates 230a, 230b, 2300 and 230d, thus passing the output of the memory 40 on lines 90a, 90b, 900 and 90d through inverters 236a, 236b, 2360 and 236d to the reset inputs of the flip-flops 2400, 240b, 2400 and 240d of the counter 72. The outputs of the flipflops 240a, 240b, 2400 and 240d are changed from their full count to a lower count which is the inverse of the twos complement of the selected telephone digit to produce a high output from NAND gate 242 over line 108. Oscillator pulses are applied through line 112 to the input of the flip-flop 240a to reduce the count in the counter 72. Once the counter in the counter 72 reaches the full count, the NAND gate 242 again produces a low output terminating the production of telephone pulses. Upon the output of the NAND gate 242 going negative, the NOR gate 244 produces a positive output enabling the NAND gate 246. Simultaneously, the'low output on line 108 triggers the one-shot 248 producing a low output which disables the NAND gate 246 for a duration corresponding to the selected duration between successive trains of telephone pulses. After the operation of the one-shot 248, the NAND gate 246 is operated in the event that the line 107 is high indicating that the additional numbers have been read into the memory 40.

Referring now to FIG. 8, the output of the oscillator on line 1 12 operates the transistor 278 which pulses the relay coil 282 causing the dialing pulses contact 286 to open and close a circuit between the terminals 288 and 290 in series with the telephone lines TIP and RING to dial a telephone number. With'each operation of the coil 282, the contacts 294 close, thus shorting out the terminals 296 and 298 across the hand-held telephone receiver preventing undue noise in the operators ear.

When the hand-held receiver is on the hook switch, the switch 309 is operated disconnecting the contact arm 316 from the contact 315 and engaging the contact 318 to complete a circuit from the TIP conductor through terminal 307, line 46, resistor 346, contact 344, contact arm 342, line 48, contact 318 and contact arm 316 to the positive terminal of the battery 317. A charging circuit for the battery 317 is completed through negative terminal of the battery 317 through the diode 320 and terminal 310 to the RING conductor. When the hook switch 309 is allowed to return to its normal position by lifting the hand-held receiver, the contacts 308 close thus completing the dialing circuit from the TIP conductor through the diode 304, terminal 288, dial pulse contacts 286, terminal 290, the receiver and contacts 308 back to the RING conductor. Also, when the hook switch 309 returns to its normal position, the contact arm 316 disengages the contact 318 thus opening the charging circuit to the battery 317 and connecting the battery 317 through the contact arm 316, contact 315 and contacts 313 to the line 44 and the voltage terminal 164. When the voltage between the TIP conductor and the RING conductor reverses upon the called party answering his telephone, the diode 304 becomes non-conductive and current is passed through the resistor 301 and the relay 302 thus opening the contacts 313 to conserve the power of the battery 317 to prevent discharge during the time that the telephone is being used in normal conversation.

In the function control circuit 42, shown in FIG. 8, the manual mode is selected by the switch 326 having its contact arm 324 engaging the contact 328 to apply a voltage from line 44 to line 52. When the switch 326 is in a position identified as automatic mode, the contact arm 324 engages the contact 330 applying voltage to contact arm 334 and contact 348 of the switch. 336 to enable the switch 336 to select a call mode. In the record mode, the contact arm 342 engages the contact 348 and the contact arm 334 engages the contact 340 to supply voltage from the line 48 and battery 317 through contact arm 342, contact 348, contact arm 334 and contact 340 to line 56. For the record mode the hook switch 309 is in its operated position, i.e., the hand-held receiver in place to connect the contact arm 316 with the contact 318. In the call mode the hook switch 309 has its contact arm 316 engaging contact 315, i.e., receiver raised, and the contact arm 334 engages the contact 338 supplying voltage from the battery 317 through contact arm 316, contact 315, contacts 313, contact arm 324, contact 330 contact arm 334 and contact 340 to the line 56.

The clear circuit 62, shown in FIG. 9, is triggered by the application of the voltage to the terminal 164 and the line 44 by the initial operation of the hook switch 309 when a hand-held receiver is lifted from the telephone instrument. The signal on line 44 is applied by the resistor 356 to charge the capacitor 358 until the breakdown voltage of the zener diode 360 is reached whereupon the transistor 362 becomes conductive triggering the one-shot 368. The one-shot 368 produces clear signals on the lines 64 and to clear various circuit portions in the telephone number generator.

When the function circuit 42 is in either the record mode or call mode and the operator selects a telephone number in the repertory circuit 32 by depressing a push-button switch the address gate circuit 26 in FIG. 10 is activated. In particular, the output of the bounce elimination circuit 28 on line 123 is applied through NOR gate 372 to gate the binary coded signals on lines 22a, 22b, 22c and 22d through the NAND gates 374a, 374b, 3740 and 374d to the lines 138a, 138b, 1380 and 138d. The NAND-function gate 376 senses the presence of a sig nalfon any of'the outputs of the NAND. J gates 374a, 374b,}.74c and 374d to produce a-s'igrial on erase signal to line' i44QThe program signalon line 56 enables'the NAND gate 442 which, at the end of a line 312 which has atrailing edge to trigger the flip-flop r 378. A first output of the fliprflo'p 378 is applied to the second input of-the NOR gate3 li2ftjo prevent further signals on line -l23 from gating the NAND gates 374a, 374b, 3740 and 374d; thus onlytthe first digit produced jby tlie push-button switches r'ssa through 158j (FIG.

" 2f), after a reset cycle from theclear circuiti1l6 (FIG.

" 1), is allowed to pass thrcgugh the addres's'gatecircuit 26. i 6 ln the memory address} 20, thesign al' on line l'l 32 is appliedt'pfthe dela cii'cuit through the-re sisor380'and the capacitor o trigger the one-shot; 384. A first" output of the 0 hot 384 applies a binary one to'first input ofthe co unter unit 392'. The binaryto -decinial decoder 386 in response to signals on lines 138a, 138b,"

138C and 138d produces out'putswhic'hxare encoded by the NA'ND-gunction gates 388a"throug h"38 8h and ap f plied remaining-data'inputs' ofjthe:'counteriunit 392 and the data ,inputsfofthe counter unit 394 and clearfsig nallis applie d ovjer line 118. W th theisignal producedon line couhtingsignal onieith'er-line 134 or line 136, produces 130 at the trailing edge of'thefirst binary coded signal applied; to lines 22a, 212b; 22c and2-2d,;the NAND gate 4 56is enabled to allow asub'sequent pulse on line 123 from a subsequent binary signallappliedto-lines' 22a; 22b, 22 and 22d to trigger the'one shot 46 2 and apply a pulse over 7 line l29 'to the preset input of the parallelto serial conflip-flop 396.,Th'e second output of the one-shot' 384 w sets the selectedbinary'address from the first output of the one-shot? 384 and NAND-function gates 388a 1 through '388h into the counter 397. The table of'EIG, 1 10 illustrates thefselectedbi naryaddresses correspond ing to the selectedrdecilrnial digits of the push-button ejn coder (FIG, ;1;) Theaddress in th e counter 39'7fap plied to lines 154a through-154j is stepped up oradm t ];t'or.474 to trigger. the one-ishot476g A first output of the vanced by clock pulsesjoniline 134. The initial selected? M t one-shot 476 operates -the NAND gatej 468 and the addresses in the counter 3 97 are separated by 44 biliarydigits, thusallowinga block-ofad'dresses which is suffi- 1 cient to store elvenjbinarycodeddecirnal digits;

Referring to FlGhlL 'the signal online l 32caujs ed v the first digit, selecting ,hiembr l alongwith theprogranrsignal on line 56 tofthe input of 1 'therNANl) gate 404ihjth'e autorria'tic control'circuit 58. The pulse 0m h; tl' 1e "NAN JD gatev 404 goe's low which at its trailingend applies positivepulse through the differentiating ci'rcuit corisisting'of capacitor40j6aand resistors 408 and4l0 and the 'N'OR gateAIZto the clear inputs of flip flops j4l 4a-throughl4l4fin 't'he bif nary counter'416; When the counter 416 isres'et thelf. NAND gate 420 sensesja count'fothervthan 44fproduc-- ing ahigh' outputwhichclears"theiflip flop466iaswell as applying an enable signal through 'NAND gateAZ Z" 1 Y and NAND-function gate ",424fto thei osc-illator 426 which begins 'producingclock pulses; The pulse output,

from the oscillator 426 is applied through the NAND Qgate .430, which is enabled by'the first outputof flip- 1: flop 434, to the line 134 to up-input of the counter-392 (FIG. 10). Also, the output of the oscillator-426isYap' plied by inverter 428 to an input of thefflip-flop 4l4q which advances the countin the counte'r416 until the count in thecounter reaches 44 causing the outputiof 1 the NAND gate 420 to go low which through th e NANDigate 432 triggers the flip-flop.434.ZThgNAND V a g gate 432 is enabled by the prograin; signalon li'ne- .56. With the flip-flop434 being triggeredj its secondoutq -put operates the one-shot470,applying-a signalthroiigh verter 30 (FIG. 1 thus setting the stages of the parallel-to-serial"coijv etter 30 in'accordance with the binary coded signal on lines 22:1,.22b, 22c. and 22d. Also, the output of the NAND gate'456-triggers the flip-flop 466 whose outputsdisable the NAND gate 422 and enable 466trigg'ers' theone-shot 470 which clears the flip-flops V 4l4a through 4l4f andthe counter 4 16. The output of V thefNAND gate-456 through; the resistor 472 is caused I tojbe delayedjslightlyfby thecharge time of the capaci- NAND-function gatex424to the oscillator 426. The

,four-fpiulse outputiofy the ,oscillatorf 426 is applied the NOR gate 412 to clearthe'fflip flops414 a through 4l4f in thecounter 416 thus "initiating another full count cycle through the NAND gate-420, NAND gate 422 and the NAND-'functiongate 424 to the oscillator 426. The flip-flop 434 enables the downNAND gate 438 which applies count-down signals to the line 138 q a and disables the NAND gatc43llaswell as applying an ation isapplied-i L t hroug'h line 131' to the clockinput of theparallel-tos er iallo onverterBOIFIG 1) whichserially reads out the binary'c'oded digits therein and applies them over line- T 5?! 146 to .the NORJgare F148 andfthe data' input 6f the memory 150. Similarly;hsubsequent'jpfulselsignals on lirie123 in responsetolslirnilarly selected binary coded f (decimal digits on lines'22d 22b, 22ic ha 22d no. 1)"

, willibe r'eadinto successive bloks'ioff four locations in y r a the nier'nory 150 untilthe counter 4 l 6reachesa count A "iof 44--whe'reupon the NANDgate 420 operates reset. 1

e ting the flip-flop 466 to disablefurther?operationof the 7 i osci'l-lat orj 426. Additional telephonefnumbers can be 'read ihtoithe repertory cir uit- 32' operating the switch- 326 (F-lGJS).orteinporarillyloperating the hook switch309 tojcause aclears ignal onJlincs ll8arid'122,

- *yhwhn a eall sigha-l 'is applied to, line',54, thefNANli) gate484is ah1eem pass'a signal from line123 to in.

'verte rf464 and the flip-flop 46.6 enabling gate '468 and I ldisablir igga'te, 422. The operationlofw-the flip-flop 466 also triggers the one shot 470clearing the' c'ounter 416.

Alsorth e output of the NAND gate 484 triggers "the on'e' shotl 476 causing the operationof the "oscillator again operates the one-"shot 4 76Tb eginning another 1 cycle of four pulses of the oscillator 426The operation 0f the automatic controlcirc'uit-58 continues until'the county it'l the counter 416 reaches 441, terminating the operation ofthe automatic control circuit.

7 In the automatic read circuit 36 shownin FlGflL the serial information read on the line l56hfromfthe memory data output is clocked intofth'esuccessive stages 492a, 492b,-492c and 492d of the shift register 494 by the clock pulses on line 128 through NAND gate 490 which is enabled by the call signal on line 54. After the serial binary coded decimal signal has been read into the successive stages or flip-flops 492a, 492b, 492e, and 492d, the one-shot 498 enabled by the call signal on line 54, is operated by the signal on line 124. The first output of the one-shot 498 operates gates 500a, 500b, 500c and 500d to gate the outputs of the registers 492a, 492b, 4920 and 492d to the lines 34a, 34b, 34c and 34d. After operation of the one-shot 498 a signal is applied to the line 126 causing the automatic control circuit 58 to control the read out of a subsequent number from the memory 150 to the line 128.

Since many modifications, variations, and changes in detail may be made to the present embodiment, it is intended that all matter in the foregoing description and shown in the drawings be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. An apparatus for generating signals corresponding to digits of a selected telephone number on a telephone line comprising a single push-button keyboard including pushbutton switches,

switch means for selecting a record mode or a call mode,

memory means for receiving and storing representations of a plurality of telephone numbers in selected locations of the memory means, each of the plurality of telephone numbers having a plurality of digits,

means responsive to a first operation of the pushbutton switches when the switch means is in the record mode or the call mode for selecting a location in the memory means,

means responsive to subsequent operation of the push-button switches in accordance with the selected telephone number when the switch means is in the record mode for storing representations of the selected telephone number in the selected location in the memory means,

means responsive to the receipt of a representation of a digit for producing signals on the telephone line corresponding to the received representation of the digit, and

means responsive to the memory location selecting means when the switch means is in the call mode for applying the representation of digits from the selected location to the signal producing means.

2. An apparatus as claimed in claim 1 wherein said switch means also has a manual mode, and

there is included means responsive to the switch means in the manual mode for gating representations of selected digits from the push-button keyboard to the signal producing means.

3. An apparatus as claimed in claim 1 including delay means responsive to the first operation of the push-button switches for preventing operation of the memory location selecting means and storing means until after an initial period during which a push-button switch produces irregularities in an output signal.

4. An apparatus as claimed in claim 2 wherein the signal producing means includes a second memory for receiving and storing representations of digits from the push-button keyboard during the manual mode or from the first memory means during the call mode, a register, means for applying representations of digits from the second memory means to the register to produce a corresponding count in the register, and

oscillator means for generating dial pulse signals to form a pulse train having a number of pulses corresponding to the count in the register.

5. An apparatus as claimed in claim 1 wherein the memory location selecting means includes gating means for passing the representation of a first selected digit, and

means operated at the termination of the representation of the first selected digit for disabling the gating means to block subsequent representations of selected digits.

6. An apparatus as claimed in claim 5 wherein the disabling means disables the memory storing means and the applying means until the termination of the representation of the first selected digit.

7. An apparatus as claimed in claim 5 wherein the memory location selecting means includes an address counter, and means responsive to a representation of a first selected digit from the keyboard for setting the counter to a selected count corresponding to the first selected digit spaced from the other selected counts by at least the number of digits in the telephone number;

the storing means includes'means for sequentially stepping the count in the counter in response to each subsequent operation of the push-button switches; and

the applying means includes means for sequentially stepping the count in the counter a predetermined.

duration after the representation of a digit from a selected address has been applied to the signal producing means.

8. An apparatus as claimed in claim 7 which includes means for counting the number of steps of the address counter preventing reading or writing in an adjacent memory location.

9. An apparatus as claimed in claim 8 whichincludes means responsive to a first operation of the pushbutton switches when the switch means is in the record mode for sequentially stepping the address counter up and down through the selected memory location, and

means for applying erasing signals to erase any digit stored in the selected memory location during the stepping down of the address counter.

10. An apparatus for applying trains of pulses corresponding to digits of a selected telephone number to a telephone line, comprising a single push-button keyboard including ten pushbutton switches capable of being selected in accordance with selected digits;

encoding means responsive to operation of the pushbutton switches for producing parallel binary representations relating to the selected digits;

function control switch means for selecting a manual mode, a record mode or a call mode;

a first random access memory having parallel binary inputs for receiving binary representations, a plurality of storage locations for storing binary representations, and parallel binary outputs;

gating means operated by the function control switch means in the manual mode for applying the binary representations from the encoding means to the first-memory inputs;

write means responsive to parallel binary representations of digits sequentially applied to the firstmemory inputs for selecting respective sequential storage locations in the first memory to store the binary representations applied to the first-memory inputs in the respective sequential first-memory storage locations;

read means operable to apply parallel representations of stored binary representations in the respective sequential first-memory storage locations to the first-memory outputs;

a first counter having means for receiving parallel binary representations from the first-memory outputs to produce a corresponding count in the counter;

oscillator means for generating telephone dialing pulses;

means for applying the dialing pulses to the first counter to change the count in the first counter;

control means responsive to the count in the first counter being other than a predetermined count for enabling the oscillator means;

said control means being responsive to the count in the first counter being equal to the predetermined count for disabling the oscillator means and for operating the read means;

a second random access memory having a serial binary input, a plurality of storage locations for storing binary representations and a serial binary outa second counter for selecting individual secondmemory storage locations;

means responsive to a first operation of the pushbutton switches when the function control switch means is in the record or call mode for setting the second counter to a selected count which is spaced from other selected counts by at least the number of bits in a telephone number;

means responsive to subsequent operation of the push-button switches when the function control switch means is in the record mode for converting the parallel binary coded decimal representations from the encoding means to serial binary representations;

clock means for sequentially stepping the count in the second counter through four counts;

write means for applying the serial binary representations from the parallel-to-serial converting means to the second-memory serial input in synchronism with the clock means;

means connected between the second-memory serial output and the first-memory parallel inputs for converting serial binary representations to parallel binary representations; and

read means responsive to termination of the first operation of the push-button switches when the function control switch means is in the call mode for operating the clock means and the serial-to-parallel converting means in synchronism. 

1. An apparatus for generating signals corresponding to digits of a selected telephone number on a telephone line comprising a single push-button keyboard including 10 push-button switches, switch means for selecting a record mode or a call mode, memory means for receiving and storing representations of a plurality of telephone numbers in selected locations of the memory means, each of the plurality of telephone numbers having a plurality of digits, means responsive to a first operation of the push-button switches when the switch means is in the record mode or the call mode for selecting a location in the memory means, means responsive to subsequent operation of the push-button switches in accordance with the selected telephone number when the switch means is in the record mode for storing representations of the selected telephone number in the selected location in the memory means, means responsive to the receipt of a representation of a digit for producing signals on the telephone line corresponding to the received representation of the digit, and means responsive to the memory location selecting means when the switch means is in the call mode for applying the representation of digits from the selected location to the signal producing means.
 2. An apparatus as claimed in claim 1 wherein said switch means also has a manual mode, and there is included means responsive to the switch means in the manual mode for gating representations of selected digits from the push-button keyboard to the signal producing means.
 3. An apparatus as claimed in claim 1 including delay means responsive to the first operation of the push-button switches for preventing operation of the memory location selecting means and storing means until after an initial period during which a push-button switch produces irregularities in an output signal.
 4. An apparatus as claimed in claim 2 wherein the signal producing means includes a second memory for receiving and storing representations of digits from the push-button keyboard during the manual mode or from the first memory means during the call mode, a register, means for applying representations of digits from the second memory means to the register to produce a corresponding count in the register, and oscillator means for generating dial pulse signals to form a pulse train having a number of pulses corresponding to the count in the register.
 5. An apparatus as claimed in claim 1 wherein the memory location selecting means includes gating means for passing the representation of a first selected digit, and means operated at the termination of the representation of the first selected digit for disabling the gating means to block subsequent representations of selected digits.
 6. An apparatus as claimed in claim 5 wherein the disabling means disables the memory storing means and the applying means until the termination of the representation of the first selected digit.
 7. An apparatus as claimed in claim 5 wherein the memory location selecting means includes an address counter, and means responsive to a representation of a first selected digit from the keyboard for setting the counter to a selected count corresponding to the first seleCted digit spaced from the other selected counts by at least the number of digits in the telephone number; the storing means includes means for sequentially stepping the count in the counter in response to each subsequent operation of the push-button switches; and the applying means includes means for sequentially stepping the count in the counter a predetermined duration after the representation of a digit from a selected address has been applied to the signal producing means.
 8. An apparatus as claimed in claim 7 which includes means for counting the number of steps of the address counter preventing reading or writing in an adjacent memory location.
 9. An apparatus as claimed in claim 8 which includes means responsive to a first operation of the push-button switches when the switch means is in the record mode for sequentially stepping the address counter up and down through the selected memory location, and means for applying erasing signals to erase any digit stored in the selected memory location during the stepping down of the address counter.
 10. An apparatus for applying trains of pulses corresponding to digits of a selected telephone number to a telephone line, comprising a single push-button keyboard including ten push-button switches capable of being selected in accordance with selected digits; encoding means responsive to operation of the push-button switches for producing parallel binary representations relating to the selected digits; function control switch means for selecting a manual mode, a record mode or a call mode; a first random access memory having parallel binary inputs for receiving binary representations, a plurality of storage locations for storing binary representations, and parallel binary outputs; gating means operated by the function control switch means in the manual mode for applying the binary representations from the encoding means to the first-memory inputs; write means responsive to parallel binary representations of digits sequentially applied to the first-memory inputs for selecting respective sequential storage locations in the first memory to store the binary representations applied to the first-memory inputs in the respective sequential first-memory storage locations; read means operable to apply parallel representations of stored binary representations in the respective sequential first-memory storage locations to the first-memory outputs; a first counter having means for receiving parallel binary representations from the first-memory outputs to produce a corresponding count in the counter; oscillator means for generating telephone dialing pulses; means for applying the dialing pulses to the first counter to change the count in the first counter; control means responsive to the count in the first counter being other than a predetermined count for enabling the oscillator means; said control means being responsive to the count in the first counter being equal to the predetermined count for disabling the oscillator means and for operating the read means; a second random access memory having a serial binary input, a plurality of storage locations for storing binary representations and a serial binary output; a second counter for selecting individual second-memory storage locations; means responsive to a first operation of the push-button switches when the function control switch means is in the record or call mode for setting the second counter to a selected count which is spaced from other selected counts by at least the number of bits in a telephone number; means responsive to subsequent operation of the push-button switches when the function control switch means is in the record mode for converting the parallel binary coded decimal representations from the encoding means to serial binary representations; clock means for sequentially stepping the count in the second counter through four counts; write means for applying the serial binary representations from the parallel-to-serial converting means to the second-memory serial input in synchronism with the clock means; means connected between the second-memory serial output and the first-memory parallel inputs for converting serial binary representations to parallel binary representations; and read means responsive to termination of the first operation of the push-button switches when the function control switch means is in the call mode for operating the clock means and the serial-to-parallel converting means in synchronism. 